摘要
利用常规气象观测资料、自动站加密观测资料和NCEP 1°×1°逐6 h的再分析资料以及卫星云图、雷达探测资料,对2014年5月8—10日华南暖区暴雨过程的成因进行了初步探讨,同时对这次暴雨过程的EC、T639、JAPAN模式的预报性能也进行了检验等,结果表明:1边界层西南急流、东南风急流造成的强烈辐合与广东珠三角地区的强降水关系密切;2在有利的天气尺度环境条件下,相继发展的MCS具有明显的Back-Building特征,MCS的低质心结构表明对流系统具有明显的热带季风暖云对流性质,具有极高的降水效率,有利于造成局地较高的累积降水量;3数值模式对影响系统及降水量级的预报存在一定偏差,尤其对强降水落区和强度的预报仍需进一步订正,预报员受数值模式预报结果影响,对暴雨和大暴雨在华南中东部存在明显的空报。对8日的暴雨过程的中尺度数值模拟表明,降水物理方案的选择对于暖区对流系统的发生发展影响明显,试验结果表明在采用WM6的微物理方案下,母网格采用Grell对流参数化方案的Run02试验降水模拟结果最为理想,一定程度上反映了暖区对流系统演变状况。
From May 8th to lOth,a large area heavy rain appeared in South China,which covered large area, lasted long time, had local rainfall intensity and had the obvious rainstorm characteristics of warm area. The rain- storm of warm area was directly related to multiple successive development of mesoscale convective system （MCS） activity. From 8th to 9th, short wave disturbance in middle and high altitude went through the area of Southern Chi- na, southwesterly flowed in low altitude enhanced, of which the humidity increased significantly in the boundary lay- er for the warm and moist advection transported, convective instability enhanced, was conducive to the development of convection system in warm zone. During the period from afternoon to night on 10th, South China was controlled by divergent flow in upper westerly jet exit region, convection in warm zone near Yangjiang and in front of the cold front were significantly developed. Synoptic analysis indicated that the strong convergence caused by southwesterly and southeasterly jet in boundary was closely related to the heavy rainfall in Guangdong Pearl River Delta region. Under the favorably synoptic environment condition, satellite and radar observations indicated obviously Back - building characteristics of successive development of MCS. Low barycenter fabric of MCS indicated that convection system had obvious tropical monsoon warm cloud convection nature, which had a very high precipitation efficiency and was conducive to result in higher local accumulation of precipitation. Numerical model had a level of bias to forecast precipitation and affecting systems, in particular, the prediction of strong precipitation area and intensity needed fur- ther correction;There was obvious false alarm for the prediction of storms and heavy rain making by forecasters whom were influenced by numerical model in the central and eastern of Southern China. Mesoscale numerical simu- lation for the storm on 8th indicated that the development of convection system in warm area was sign
出处
《贵州气象》
2016年第4期44-51,共8页
Journal of Guizhou Meteorology
基金
中国气象局气象关键技术集成与应用项目"气象预报科研业务结合"(CMAGJ2013ZX-ZH1)资助
